The present invention relates to cooling electrical printers particularly matrix printers wherein the electrical and electronic components are compactly arranged within a small space.
Cooling of equipment of the type to which the invention pertains is essentially a process for removing thermal energy produced by electric current. This thermal energy is a loss and is produced by and in electrical resistances. Unless the operation of the printer can be carried out at a fairly low temperature, long lasting operation and inadequate heat removal will cause the electrical and particularly the electronic components to become unduly heated and ultimately they will fail. Excessive heating is a cumulative process of deterioration towards failure.
Generally it is known in electronic equipment and in matrix printers in particular to provide forced cooling through a built-in fan. The various electrical components as well as mechanical mounting structure for these components, such as the matrix printhead, will be provided with heat dissipating surfaces such as cooling ribs which will be exposed to the air current from the fan so as to enhance the heat removal process. It is necessary to arrange the components to be cooled so that they are exposed to the air flow in the most favorable fashion. Here it has to be considered that the matrix printhead moves within the printer i.e. inherently changes its position vis-a-vis the fan. Generally speaking it was found that establishing adequate air flow conditions in such printers means that in most cases the volume and space requirement is increased.
It is well known that in electronics presently there is an increasing trend towards compactness in the arrangement of the electronic components which means higher power and power requirement for the same or smaller component size. In order to economize in the manufacturing functional groups which used to be arranged on different printed circuit boards will now be compactly constructed. This tendency leads inherently to a larger density in the development of thermal energy and compactness has often lead to situation that one or the other of the electronic parts are no longer adequately enveloped by the cooling airflow.